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The TimeLord
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 Posted: Sat Jul 12, 2008 7:20 am Post subject: Re: Light has mass; That's smart |
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Am Fri, 11 Jul 2008 11:45:06 -0700 schrieb "hhc314@yahoo.com"
<hhc314@yahoo.com> in
02d33d27-90d4-41df-b168-e437c7124385@f63g2000hsf.googlegroups.com in
sci.physics.relativity:
| Quote: |
On Jul 11, 9:04Â am, "Pmb" <physics_wo...@yahoo.com> wrote:
"The Ghost In The Machine" <ew...@sirius.tg00suus7038.net> wrote in
messagenews:6hojk5-f3t.ln1@sirius.tg00suus7038.net...
In sci.physics.relativity, Benj
bjac...@iwaynet.net
wrote
on Thu, 10 Jul 2008 23:40:36 -0700 (PDT)
eced3790-71a2-4098-b444-143c5b7f4...@d77g2000hsb.googlegroups.com>:
On Jul 11, 12:07 am, Mitch Raemsch <mitch.nicolas.raem...@gmail.com
wrote:
Light does not have any kinetic energy. None of its mass comes from
its constant motion therefore it does not behave like matter.
Light's mass comes from the energy of its frequency. Matters
additional mass comes from its motion.
Light has no kinetic energy? Then how does it generate enough force
to float a glass sphere or collapse a mylar satellite?
[...]
moron.
[...]
Now in my ignorance, I am going to throw out a hypothesis that I believe
could be correct. So please SPACEMAN, please pardon me for this. Now
tested SR demonstrates and shows that particles increase with mass as
their energy increases, is it much of a stretch to assume that the
apararent mass of a photon is that of its energy content? You know, the
|
Photons have no mass. The reason is that from Relativity we know
E^2 = p^2 c^2 + m^2 c^4
and by experiment we know that
E = p c
for photons. So m=0 for photons.
| Quote: |
E = Mc^2 thing that we all learned in highschool physics.
|
E = m c^2
is true only if v=0. The reason is that for particles where m/=0 the
momentum is
p = gamma m v
with gamma = 1/sqrt[1-v^2/c^2]
If v=0 then p=0 and then (ie only if v=0) E=mc^2 from the equation above.
Note that for E=mc^2 to be valid for light, c must then be zero (because
of how this formula was derived), which it is not.
[...]
| Quote: |
Still, it is important for a lay reader here to understand that as a
physicist, I employ a great deal of logicial and mathematical
|
Physicist? Mmmmmmmm. The stuff I've presented is Phy103. Photons not
having mass is a fact established in any Phy102 class.
[...]
--
// The TimeLord says:
// Pogo 2.0 = We have met the aliens, and they are us! |
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Y.Porat
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| Posted: Sat Jul 12, 2008 7:27 am Post subject: Re: Light has mass; That's smart |
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On Jul 11, 10:03 pm, "Pmb" <physics_wo...@yahoo.com> wrote:
| Quote: |
hhc...@yahoo.com> wrote in message
news:02d33d27-90d4-41df-b168-e437c7124385@f63g2000hsf.googlegroups.com...
On Jul 11, 9:04 am, "Pmb" <physics_wo...@yahoo.com> wrote:
"The Ghost In The Machine" <ew...@sirius.tg00suus7038.net> wrote in
messagenews:6hojk5-f3t.ln1@sirius.tg00suus7038.net...
In sci.physics.relativity, Benj
bjac...@iwaynet.net
wrote
on Thu, 10 Jul 2008 23:40:36 -0700 (PDT)
eced3790-71a2-4098-b444-143c5b7f4...@d77g2000hsb.googlegroups.com>:
On Jul 11, 12:07 am, Mitch Raemsch <mitch.nicolas.raem...@gmail.com
wrote:
Light does not have any kinetic energy. None of its mass comes from
its constant motion therefore it does not behave like matter. Light's
mass comes from the energy of its frequency. Matters additional mass
comes from its motion.
Light has no kinetic energy? Then how does it generate enough force to
float a glass sphere or collapse a mylar satellite?
No dual Nobel prizes for you THIS year!
moron.
(uncle Al made me do it!)
Not to belabor the obvious, but light is also known to:
[1] spin vanes in an evacuated globe (a radiometer).
That is incorrect. It is heat that does that, i.e. one side of the vane is
black while the other is relfective. The black side heats up and thus heat
up the air inside the globe (the globe is not completely evacuated
contrary
to your assumption). If the globe were completely evacuated the friction
from the spindal would over come the extremely small force of the light..
This is all easily confirmed by noting that the vane spins in a direction
which is opposite to what it would if the torque was due to radiation
pressure.
Absolutely correct!
Snip.
In any event, I'm not sure mass comes from anything; it just is. ;-)
Though the Big Bang might be a good explanation as to where mass "comes
from".
Inertial mass is what gives a particle momentum and its momentum which
causes radiation pressure.
Pete, here you are combining apples and oranges and arriving at in
incorrect explanation.
-------------------------
I was explaining to the poster that light can have mass due to its momentum.
That seemed to be what he was talking about.
Your error is that you are mixing particles (where you are absolutely
correct) with photons which ACT in some cases like particles, but in
relaity of electromagnetic waves.
What error are you referring to? And why do you not consider a photon to be
a particle?
The fact is that electromagnetic waves sometimes seem to act like
particles (the photoelectric effect), while accelererated partcles
(say protons) have as associate De Broglie wavelenth depending on
their energy.
Both accelerated particles and photons have wave properties, and while
both acclerated particles and photons have momentum, particles have
mass while photons have none. This is an enigma that troubled even
Dr. Einstein. So don't look to Usenet for an explanation.
Depends on what you mean when you use the term "mass". It has two different
meanings depending on who is using it. I try to use the term "inertial mass"
so as to not confuse it with "proper mass" (aka rest mass). Inertial mass is
defined as the ratio of the magnitude of momentum to speed. Thus, that which
has momentum and moves will have inertial mass (but not neccesarily proper
mass)
So here is the basic enigma. Because since Maxwell, science has been
able to understand how electromagnetic radiation travels through to
void of mass free space, and though the vacuum.
Now in my ignorance, I am going to throw out a hypothesis that I
believe could be correct. So please SPACEMAN, please pardon me for
this. Now tested SR demonstrates and shows that particles increase
with mass as their energy increases, ...
That is only true if by "mass" you are referring to "inertial mass" which is
defined as m = p/v. According to your own usage of the term, a photon has
inertial mass.
is it much of a stretch to assume
that the apararent mass of a photon is that of its energy content?
Why do you call it "apparent mass" and not do the same with the velocity
dependant mass that you spoke of above?
You know, the E = Mc^2 thing that we all learned in highschool
physics.
It works for me, although I am not familiar with the experimental
physics that supports such a contention. Actually, it seems to be to
be rather basic.
Still, it is important for a lay reader here to understand that as a
physicist, I employ a great deal of logicial and mathematical
abstraction, and am sophisticated enough to not regard these as
reality. Still, mathematical abstractions can be very useful,
particularly when supported by experimental evidence. That doesn't
mean that they are reality, and this is something that lay readers
sometimes have trouble in comprehending.
Reality is something that only exists in our minds, in itself an
abstract concept. What we accept as seeing is a coordinately
collection of diffraction patterns, which out mind correlates into an
image which we accept as fact. Keep that in mind. Absolute reality is
very difficult to see.
Reality bugs me. LOL!
Pete
|
--------------------
Mr crackparoter!!
THERE IS JUST ONE KIND OF MASS!!
no one is alowed to invent new kinds of mass
just because he is unable to understand basic physics
in the MKS system there is just one K
there is not K1 and K2
got it crackparroter ??
it is not mass that is inflating with growing velocity
it is THE AMOUNT OF NEEDED ENRGY
THAT IS NEDED TO ADD VELOCITY THAT IS GROWING !!
E/gmma = ma^2
and not
E = gamma ma^2
2
the photon has mass - the only SINGLE mass that exists
no matter if you call it
inertial mass or rest mass of fucken mass !!
just one mass
3
the photon has mass (a very small mass)
and
IT IS THE ONLY MASS THAT CAN MOVE AT c !!
it is a limit **exception** case
as usual in mathematics
limit cases are special cases
many times undefined properly and in many cases - confusing
but not confusing for thinking people !!!
Y.Porat
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The TimeLord
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| Posted: Sat Jul 12, 2008 7:37 am Post subject: Re: Light has mass; That's smart |
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Am Fri, 11 Jul 2008 14:54:59 -0400 schrieb "Pmb" <physics_world@yahoo.com>
in vvWdnRIsJrQ4MerVnZ2dnUVZ_v3inZ2d@comcast.com in sci.physics.relativity:
| Quote: |
hhc314@yahoo.com> wrote in message
news:fc9b4c8d-7e19-449d-8465-aa897757c146@27g2000hsf.googlegroups.com...
On Jul 11, 9:00 am, "Pmb" <physics_wo...@yahoo.com> wrote:
"Benj" <bjac...@iwaynet.net> wrote in message
news:eced3790-71a2-4098-
b444-143c5b7f49b0@d77g2000hsb.googlegroups.com...
On Jul 11, 12:07 am, Mitch Raemsch <mitch.nicolas.raem...@gmail.com
wrote:
[...]
The energy of light is actually considered to be all kinetic.
|
Mmmmmmm. I've been thinking on this for quite a while. Kinetic energy is
energy of motion and since photons are moving with energy E=hf, that
would fit the concept. However, the mathematical treatment of kinetic
energy requires an action that usually involves mass, which the photon
does not have. Wow, what a beehive of an issue!
[...]
| Quote: |
Pete, that statement is just a little broad in my opinion. Kinetic
Energy in physics is regarded as the energy associated with mass in
motion.
Well that's how it is whether we like it or not. It comes from the
relation E = K + E_0 where E = total inertial mass, K = kinetic energy
|
Actually there is a real good article that explains it all (including
Relativity) at
http://wilson.00.andrew.home.comcast.net/energy.pdf
[...]
| Quote: |
Note: Proper mass = 0 does not mean that inertial mass = p/v is nonzero.
|
Actually it *does* mean that photons have zero mass, inertial or
otherwise.
| Quote: |
I know, just a nit. Sure I know, electromagnetic radiation has
momentum, but that does no imply that it has mass, hence it is not to a
physicist kinetic energy.
Actually it sure does - by definition! Inertial mass (*not* rest mass)
is the ratio of |momentum| to speed.
|
No, actually inertial mass is defined to be the proportionality constant
between an applied force and the resulting acceleration when the
reference frame is at rest.
[...]
--
// The TimeLord says:
// Pogo 2.0 = We have met the aliens, and they are us! |
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Y.Porat
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| Posted: Sat Jul 12, 2008 2:19 pm Post subject: Re: Light has mass; That's smart |
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On Jul 12, 2:46 am, "hhc...@yahoo.com" <hhc...@yahoo.com> wrote:
| Quote: |
On Jul 11, 6:21 pm, Mitch Raemsch <mitch.nicolas.raem...@gmail.com
wrote:
Light is a Unified force of energy.
Mitch Raemsch
Mitch, no it's not, it simply energy transmitted in the form of
electromagnetic radiation.
Harry C.
----------------------------------- |
On Jul 12, 2:02 pm, Eric Gisse <jowr...@gmail.com> wrote:
| Quote: |
On Jul 11, 11:27 pm, "Y.Porat" <y.y.po...@gmail.com> wrote:
[snip whining]
I notice you still think photons are massive.
I'll ask again - maybe you can answer me for once: What is the mass of
the photon, and how are you so sure that you can spend year after year
ranting incoherently about it?
|
----------------
since the little psychopath crook crackpotter from Alaska
Eric Shaise ........
tried to divert
my answer to his moron ng
that will be an answer to all the other civilized honest people
and not to him
1
who on earth allowed you to invent a new kind of mass
(after all even you and Pmb must admit that the photon has
'relativistic mass (( in your understanding)) ??
2
if say the electron can be accelerated very close to c
why should not a much smaller mass be accelerated to c ??
3
even according to your understandings the photon has the dimension
of mass
(mc^2 or even pc has the dimension of mass
it is in MKS the K there (kilogram
i never heard that there are two kinds of K
ie K1 and k2
4
the photon is a limit case (since there is no faster than that ..)
and the limit zone is not like the close to limit zone
even in mathematics
so *you ** cant say
that the photon **does not have mass**
5
even experimental data explorations give a result
for the smallest possible photon mass
something close to 3 x exp -31 kg ie
a bottom limit to photon mass
6
please remind the other reasons i have already forgot (:-)
ATB
Y.Porat
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Ken S. Tucker
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| Posted: Sat Jul 12, 2008 7:23 pm Post subject: Re: Light has mass; That's smart |
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On Jul 11, 4:44 pm, "hhc...@yahoo.com" <hhc...@yahoo.com> wrote:
| Quote: |
On Jul 11, 5:35 pm, "Ken S. Tucker" <dynam...@vianet.on.ca> wrote:
On Jul 11, 2:13 pm, "Sue..." <suzysewns...@yahoo.com.au> wrote:
On Jul 11, 9:00 am, "Pmb" <physics_wo...@yahoo.com> wrote:
"Benj" <bjac...@iwaynet.net> wrote in message
news:eced3790-71a2-4098-b444-143c5b7f49b0@d77g2000hsb.googlegroups.com...
On Jul 11, 12:07 am, Mitch Raemsch <mitch.nicolas.raem...@gmail.com
wrote:
Light does not have any kinetic energy. None of its mass comes from
its constant motion therefore it does not behave like matter. Light's
mass comes from the energy of its frequency. Matters additional mass
comes from its motion.
Light has no kinetic energy? Then how does it generate enough force to
float a glass sphere or collapse a mylar satellite?
The energy of light is actually considered to be all kinetic.
For every positive charge that is pushed by an emitter an
equivalent negative charge is pulled.
I get nothing but angular momentum from that.
Sue...
Well Sue, we'd need to explain how we radio
xmitter guys put power into an antenna then
it is radiated, turn on a radio.
Recall "angular momentum" is expressible as
ACTION, and energy is the Rate of Action.
You (Sue) might be right, but I thought there
was a "momentum recoil". I've read photon
thrusters max the Isp.
Regards
Ken S. Tucker- Hide quoted text -
- Show quoted text -
Ken, the ejection of a photon from a crystaline maxtrix does
demonstrate a recoil effect, but then things become rather
complicated.. This is the basis of something called the Mossbauer
effect and indeed the subject known as Mossbauer Spectroscopy.
See this link: http://en.wikipedia.org/wiki/Mossbauer_effect
Closely read the paragraph beneath the equation.
It is an extremely interesting effect, which did earn a Nobel Prize in
1961, and if you have access to old issues of Scientific American
before it was sold and began to focus on crap articles, they did
devote an entire issue to the Mossbauer Effect. If interested, find a
copy of this issue because it is well worth reading.
Harry C.
|
Hi Harry,
The issue Sue raised was the photon *only* translates
"angular momentum" implying a nil (zero) linear recoil.
My understanding is that the linear recoil momentum
has been observed spectrally, and while it is certainly
true the photon possesses the angular momentum in
unit of spin (1), it also possesses a linear momentum.
Usually Sue is not a cranky, so I was taken aback by
her post...I'll lurk a bit a see what others have to say.
Regards
Ken S. Tucker |
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Mitch Raemsch
Guest
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| Posted: Sat Jul 12, 2008 8:40 pm Post subject: Re: Light has mass; That's smart |
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|
On Jul 12, 11:23 am, "Ken S. Tucker" <dynam...@vianet.on.ca> wrote:
| Quote: |
On Jul 11, 4:44 pm, "hhc...@yahoo.com" <hhc...@yahoo.com> wrote:
On Jul 11, 5:35 pm, "Ken S. Tucker" <dynam...@vianet.on.ca> wrote:
On Jul 11, 2:13 pm, "Sue..." <suzysewns...@yahoo.com.au> wrote:
On Jul 11, 9:00 am, "Pmb" <physics_wo...@yahoo.com> wrote:
"Benj" <bjac...@iwaynet.net> wrote in message
news:eced3790-71a2-4098-b444-143c5b7f49b0@d77g2000hsb.googlegroups..com...
On Jul 11, 12:07 am, Mitch Raemsch <mitch.nicolas.raem...@gmail.com
wrote:
Light does not have any kinetic energy. None of its mass comes from
its constant motion therefore it does not behave like matter. Light's
mass comes from the energy of its frequency. Matters additional mass
comes from its motion.
Light has no kinetic energy? Then how does it generate enough force to
float a glass sphere or collapse a mylar satellite?
The energy of light is actually considered to be all kinetic.
For every positive charge that is pushed by an emitter an
equivalent negative charge is pulled.
I get nothing but angular momentum from that.
Sue...
Well Sue, we'd need to explain how we radio
xmitter guys put power into an antenna then
it is radiated, turn on a radio.
Recall "angular momentum" is expressible as
ACTION, and energy is the Rate of Action.
You (Sue) might be right, but I thought there
was a "momentum recoil". I've read photon
thrusters max the Isp.
Regards
Ken S. Tucker- Hide quoted text -
- Show quoted text -
Ken, the ejection of a photon from a crystaline maxtrix does
demonstrate a recoil effect, but then things become rather
complicated.. This is the basis of something called the Mossbauer
effect and indeed the subject known as Mossbauer Spectroscopy.
See this link: http://en.wikipedia.org/wiki/Mossbauer_effect
Closely read the paragraph beneath the equation.
It is an extremely interesting effect, which did earn a Nobel Prize in
1961, and if you have access to old issues of Scientific American
before it was sold and began to focus on crap articles, they did
devote an entire issue to the Mossbauer Effect. If interested, find a
copy of this issue because it is well worth reading.
Harry C.
Hi Harry,
The issue Sue raised was the photon *only* translates
"angular momentum" implying a nil (zero) linear recoil.
My understanding is that the linear recoil momentum
has been observed spectrally, and while it is certainly
true the photon possesses the angular momentum in
unit of spin (1), it also possesses a linear momentum.
Usually Sue is not a cranky, so I was taken aback by
her post...I'll lurk a bit a see what others have to say.
Regards
Ken S. Tucker- Hide quoted text -
- Show quoted text -
|
It has no kinetic energy. If light's energy was from its speed all
light would have the same energy. Clearly this is not true.
Mitch Raemsch |
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The Ghost In The Machine
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| Posted: Sat Jul 12, 2008 9:11 pm Post subject: Re: Light has mass; That's smart |
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In sci.physics.relativity, Pmb
<physics_world@yahoo.com>
wrote
on Fri, 11 Jul 2008 09:04:06 -0400
<kI2dnbP-q5_6x-rVnZ2dnUVZ_qbinZ2d@comcast.com>:
| Quote: |
"The Ghost In The Machine" <ewill@sirius.tg00suus7038.net> wrote in message
news:6hojk5-f3t.ln1@sirius.tg00suus7038.net...
In sci.physics.relativity, Benj
bjacoby@iwaynet.net
wrote
on Thu, 10 Jul 2008 23:40:36 -0700 (PDT)
eced3790-71a2-4098-b444-143c5b7f49b0@d77g2000hsb.googlegroups.com>:
On Jul 11, 12:07 am, Mitch Raemsch <mitch.nicolas.raem...@gmail.com
wrote:
Light does not have any kinetic energy. None of its mass comes from
its constant motion therefore it does not behave like matter. Light's
mass comes from the energy of its frequency. Matters additional mass
comes from its motion.
Light has no kinetic energy? Then how does it generate enough force to
float a glass sphere or collapse a mylar satellite?
No dual Nobel prizes for you THIS year!
moron.
(uncle Al made me do it!)
Not to belabor the obvious, but light is also known to:
[1] spin vanes in an evacuated globe (a radiometer).
That is incorrect.
|
The evacuation of course has to be very hard vacuum
in order to cancel your effect, and I'll admit to some
curiosity as to how hard that would have to be.
Best I can do is hang out a radiometer outside the ISS,
observe it for a bit, then break its seal, letting the
gas (such as it is) escape, and see if that changes
its rotational period. Of course since radiometers operate
only in gravity (the vanes sit on the tip of a pedestal), there
are some design issues here.
| Quote: |
It is heat that does that, i.e. one side of the vane is
black while the other is relfective. The black side heats up and thus heat
up the air inside the globe (the globe is not completely evacuated contrary
to your assumption). If the globe were completely evacuated the friction
from the spindal would over come the extremely small force of the light.
This is all easily confirmed by noting that the vane spins in a direction
which is opposite to what it would if the torque was due to radiation
pressure.
|
Hm...I'll definitely have to calculate that. You're right
in that the effect would be rather tiny, since p = E/c.
Even if one assumes "panes" 1m^2 in area (that would
tower over a person), one only gets 1250 W of power,
and a momentum shift of 4.17 * 10^-6 kg-m/s per second.
One would only need 14 micrograms per second (at 300 m/s) to
counteract that. I'm not up on my temperature versus velocity and have
not had my morning coffee yet, though. ;-)
| Quote: |
[2] eject electrons from a sensitive surface (photoelectric effect).
[3] heat things; granted, this one might be explained by
thermal rather than kinetic, but what is thermal but a
submicroscopic jiggle?
[4] wiggle electrons in a coil or antenna, feeding an amplifier.
Granted, that one might be explained by magnetic or electric,
rather than kinetic.
In any event, I'm not sure mass comes from anything; it just is. ;-)
Though the Big Bang might be a good explanation as to where mass "comes
from".
Inertial mass is what gives a particle momentum and its momentum which
causes radiation pressure.
|
But light doesn't have inertial mass ... ??
--
#191, ewill3@earthlink.net
Windows Vista. Now in nine exciting editions. Try them all!
** Posted from http://www.teranews.com ** |
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Y.Porat
Guest
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| Posted: Sun Jul 13, 2008 8:52 am Post subject: Re: Light has mass; That's smart |
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On Jul 11, 6:45 pm, Uncle Al <Uncle...@hate.spam.net> wrote:
| Quote: |
Mitch Raemsch wrote:
Light does not have any kinetic energy. None of its mass comes from
its constant motion therefore it does not behave like matter. Light's
mass comes from the energy of its frequency. Matters additional mass
comes from its motion.
Mitch Raemsch
Fucking imbecile.
http://prola.aps.org/abstract/PRL/v90/i8/e081801
Phys. Rev. Lett. 90 081801 (2003)
Phys. Rev. Lett. 80 1826 (1998)
Phys. Rev. Lett. 68 23 3383 (1992)
Phys. Rev. D 8 2349 (1973)
Photon rest mass is less than 10^(-51) grams or 7x10^(-19) electron
volts. If the photon had non-zero rest mass then electromagnetism
would have a finite range and force proportional to 1/r^2 would not
obtain.
---------------------------------- |
so it has a rest mass
and how many kinds of mass you are going to invent now ??
crackparroter
2
the photon is a limit case
an exception case
is it completely out of consideration for you ??
like
it is the only mass that can move at c
if the electron can reach velocities very close to c
why should not a mass as you parroted above-
cannot reach exactly c ???!!!
does such a big idea is beyond your ability ??
Mr big creator and inventor ???
ATB
Y.Porat
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Pentcho Valev
Guest
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| Posted: Sun Jul 13, 2008 6:29 pm Post subject: Re: Light has mass; That's smart |
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On Jul 13, 8:00 pm, Tom Roberts <tjroberts...@sbcglobal.net> wrote:
| Quote: |
Pmb wrote in sci.physics:
There is only one meaning to the term "mass" and that's m = p/v.
[Be careful to define division of 3-vectors; say rather
that "mass" is the m in p=mv.]
In Newtonian mechanics this is one of the many meanings of "mass", and
perhaps it is the defining one, perhaps not. The problem is that there
are many different aspects of "mass" that are all the same in Newtonian
mechanics, but are different in relativity.
|
Newtonian mechanics is so dull and relativity is so exciting, aren't
they Honest Roberts:
http://en.wikipedia.org/wiki/Mass_in_General_Relativity
"The concept of mass in general relativity (GR) is more complex than
the concept of mass in special relativity. In fact, general relativity
does not offer a single definition for the term mass, but offers
several different definitions which are applicable under different
circumstances. Under some circumstances, the mass of a system in
general relativity may not even be defined."
Pentcho Valev
pvalev@yahoo.com |
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Pmb
Guest
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| Posted: Sun Jul 13, 2008 6:47 pm Post subject: Re: Light has mass; That's smart |
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"Y.Porat" <y.y.porat@gmail.com> wrote in message
news:494a4cb9-367c-4e75-9c43-6ddab568eba3@l64g2000hse.googlegroups.com...
| Quote: |
http://prola.aps.org/abstract/PRL/v90/i8/e081801
Phys. Rev. Lett. 90 081801 (2003)
Phys. Rev. Lett. 80 1826 (1998)
Phys. Rev. Lett. 68 23 3383 (1992)
Phys. Rev. D 8 2349 (1973)
Photon rest mass is less than 10^(-51) grams or 7x10^(-19) electron
volts. If the photon had non-zero rest mass then electromagnetism
would have a finite range and force proportional to 1/r^2 would not
obtain.
----------------------------------
so it has a rest mass
and how many kinds of mass you are going to invent now ??
crackparroter
---------------------------------- |
Nobody is "inventing" fifferent kind of masses. The term "rest mass" (aka
"proper mass") refers to the mass (aka "inertial mass" or "relativistic
mass") of a particle at rest. This is like the term "proper time" which
refers to the time recorded on a clock which passes through two events on a
particular world line.
There is only one meaning to the term "mass" and that's m = p/v. Anything
else is a redefinition of the term or a particular case of that term. E.g.
its known that m = m(v). The term "rest mass" refers to the case v = 0 and
thus m_0 = m(0), i.e. a particular case.
Different worldlines - different proper times. And because the rest mass is
less than a certain value does not imply that its not zero. The zero value
of the proper mass has not be verified experimentally. I doubt that it can
be verified.
| Quote: |
if the electron can reach velocities very close to c
why should not a mass as you parroted above-
cannot reach exactly c ???!!!
|
Because anything which has non-zero rest mass would take an infinite amount
of energy to obtain the speed of light. Most people here know that.
| Quote: |
does such a big idea is beyond your ability ??
Mr big creator and inventor ???
|
Why the flaming?
Pete |
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BURT
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| Posted: Sun Jul 13, 2008 7:03 pm Post subject: Re: Light has mass; That's smart |
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On Jul 13, 10:00 am, Tom Roberts <tjroberts...@sbcglobal.net> wrote:
| Quote: |
Pmb wrote:
There is only one meaning to the term "mass" and that's m = p/v.
[Be careful to define division of 3-vectors; say rather
that "mass" is the m in p=mv.]
In Newtonian mechanics this is one of the many meanings of "mass", and
perhaps it is the defining one, perhaps not. The problem is that there
are many different aspects of "mass" that are all the same in Newtonian
mechanics, but are different in relativity. The most common and and most
useful generalization to relativity is: 3-vectors => 4-vectors. Then
"mass" is the m in P=mV; m is trivially invariant.
One advantage of this approach over yours is that it is directly
applicable to GR, but yours isn't. Moreover, this approach is also
applicable to QED, and yours isn't useful there, either. And, of course,
it retains mass as an intrinsic property of an object, which your
approach does not.
Tom Roberts
|
Mass is the amount of concentrated energy in a point particle or C^2.
Accelerating it raises its concentrated energy above C^2 by the Gamma
factor.
Mitch Raemsch |
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BradGuth
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| Posted: Sun Jul 13, 2008 10:39 pm Post subject: Re: Light has mass; That's smart |
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On Jul 13, 11:29 am, Pentcho Valev <pva...@yahoo.com> wrote:
| Quote: |
On Jul 13, 8:00 pm, Tom Roberts <tjroberts...@sbcglobal.net> wrote:
Pmb wrote in sci.physics:
There is only one meaning to the term "mass" and that's m = p/v.
[Be careful to define division of 3-vectors; say rather
that "mass" is the m in p=mv.]
In Newtonian mechanics this is one of the many meanings of "mass", and
perhaps it is the defining one, perhaps not. The problem is that there
are many different aspects of "mass" that are all the same in Newtonian
mechanics, but are different in relativity.
Newtonian mechanics is so dull and relativity is so exciting, aren't
they Honest Roberts:
http://en.wikipedia.org/wiki/Mass_in_General_Relativity
"The concept of mass in general relativity (GR) is more complex than
the concept of mass in special relativity. In fact, general relativity
does not offer a single definition for the term mass, but offers
several different definitions which are applicable under different
circumstances. Under some circumstances, the mass of a system in
general relativity may not even be defined."
Pentcho Valev
pva...@yahoo.com
|
Special conditional laws of physics are required in order to
continually snooker and dumbfound humanity for all it's worth. It
also helps if you are Jewish, as otherwise discovering the absolute
holy grail of the god particle, the mass of a photon, or even that of
dirt cheap fusion energy will not likely get you a Nobel.
- Brad Guth Brad_Guth Brad.Guth BradGuth |
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Tom Roberts
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| Posted: Sun Jul 13, 2008 11:00 pm Post subject: Re: Light has mass; That's smart |
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Pmb wrote:
| Quote: |
There is only one meaning to the term "mass" and that's m = p/v.
|
[Be careful to define division of 3-vectors; say rather
that "mass" is the m in p=mv.]
In Newtonian mechanics this is one of the many meanings of "mass", and
perhaps it is the defining one, perhaps not. The problem is that there
are many different aspects of "mass" that are all the same in Newtonian
mechanics, but are different in relativity. The most common and and most
useful generalization to relativity is: 3-vectors => 4-vectors. Then
"mass" is the m in P=mV; m is trivially invariant.
One advantage of this approach over yours is that it is directly
applicable to GR, but yours isn't. Moreover, this approach is also
applicable to QED, and yours isn't useful there, either. And, of course,
it retains mass as an intrinsic property of an object, which your
approach does not.
Tom Roberts |
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Autymn D. C.
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| Posted: Mon Jul 14, 2008 1:29 am Post subject: Re: Light has mass; That's smart |
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On Jul 11, 11:45 am, "hhc...@yahoo.com" <hhc...@yahoo.com> wrote:
| Quote: |
Your error is that you are mixing particles (where you are absolutely
correct) with photons which ACT in some cases like particles, but in
relaity of electromagnetic waves.
The fact is that electromagnetic waves sometimes seem to act like
particles (the photoelectric effect), while accelererated partcles
(say protons) have as associate De Broglie wavelenth depending on
their energy.
|
No, waves never act as motes; the mote behavred belongs tom the matter
(elèctròns, charges) which makes the radiation.
| Quote: |
Both accelerated particles and photons have wave properties, and while
both acclerated particles and photons have momentum, particles have
mass while photons have none. This is an enigma that troubled even
Dr. Einstein. So don't look to Usenet for an explanation.
|
No again, motes hav waves; but a wave (fotòn) /is/ a wave property.
Fotòns havn't momentum; they /do/ momentum: http://egroups.com/message/free_energy/31651.
-Aut |
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Autymn D. C.
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| Posted: Mon Jul 14, 2008 1:37 am Post subject: Re: Light has mass; That's smart |
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On Jul 12, 7:19 am, "Y.Porat" <y.y.po...@gmail.com> wrote:
| Quote: |
if say the electron can be accelerated very close to c
why should not a much smaller mass be accelerated to c ??
|
I already wrote a proof for acceleration of any mass tom celerity
under wave mekanics--where speed blurs within one wave--but this is
irrelevant for the relativistic argument. Porat still doesn't know
why celerity is special. Porat, why is the speed c special?
| Quote: |
the photon is a limit case (since there is no faster than that ..)
and the limit zone is not like the close to limit zone
even in mathematics
so *you ** cant say
that the photon **does not have mass**
|
Porat still could not answer my last email at him. Yes, in maths, one
can so say the fot¨°n has no mass. $1 has no mass. 1 Hz has no mass.
1 'h' has no mass. 1 m has no mass. 1 dB has no mass. Thus, 1 ¦Ã has
no mass.
| Quote: |
even experimental data explorations give a result
for the smallest possible photon mass
something close to 3 x exp -31 kg ie
a bottom limit to photon mass
|
no, a top limit--any mass is in the background and belongs tom a
plasm¨°n, not a fot¨°n.
-Aut |
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